new build choice, 2nd gen 50w

[martin manning]

I can't see what switching functions are in your Peavy jacks, but you need something more than the usual switch contact on the tip. If there is a switch contact on a ring or ground terminal either one will work. A Cliff jack will also work.

[erwin_ve]

Marcus, are these jacks of a deuce? If so you can use the ones that had the series and parallel inputs .

[norburybrook]

thanks guy's. They are from a Deuce but I've no idea from which part, I just took anything off I though might come in useful.

Martin I've got a Cliff Stereo jack so I'll probably use that. I've just realised I've not ordered an impedance selector and my second tubetown order was already packed so they wont add it to it!...no one in the UK seems to have one......Bugger.....another $15 postage charge for $5 of parts......the third one...

Actually , thinking about it, as it's going to be a combo it doesn't matter. I'll just wire it up to whatever speaker impedance I chose, I don't need a selector.


I think I'm trying to do too many things at once here.....I've been sorting out all the stuff my new album release, finishing an album mix for a client and just started my spring tour.....

and relax.....................I have a week off for Easter, I will continue then, in a more relaxed fashion.


Marcus

[norburybrook]

I found an old FET board from a previous order/build I hadn't used.

Can someone check how I've done this as I've not used JFET before and also there's no layout/schematic for this except martins which is very different from the layout of my board.

I seem to have an unused leg of the JFET

FET.jpg

thanks

Marcus

[pompeiisneaks]

I just built a board and had to design my own, but I'm not =100% sure mines exactly like yours, one of the three is just the case, and needs directly to ground, not seeing that on yours, but that may be what that last one is. If you look at this datasheet for the NTE 452 the pin directly to the right of the tab if it's almost in your orientation is case which goes to ground.

http://www.nteinc.com/specs/400to499/pdf/nte452.pdf

I 'think' it looks right from quick review otherwise, but I would need a bit more time to look at the schematic and be sure. I don't have time right now to dig deeper, but I do think that the unused one goes to ground.

~Phil

[martin manning]

The NTE data sheet diagram shows the view from the bottom, so from the top the case terminal is to the left of the tab (Clockwise from the tab it's Case, G, D, S). Looks like you have the case and source swapped. Be prepared to adjust the source resistor to set the bias correctly, and also the resistor going from the 150k to ground to set the supply voltage Vdd. See in the files section here: http://ampgarage.com/forum/viewtopic.php?f=5&t=18389

[norburybrook]

so like this?

FET-CGDS.jpg

is this wrong then?


M

[Mr. dB]

The FET board is one thing you can pre-test before installing it in the amp. Power it up with a battery and see if it passes signal. That's one less thing to troubleshoot when the time comes to fire up the big amp.

[martin manning]

Like this...

[norburybrook]

cool, thanks Martin, that's perfect.


M

[Mr. dB]

The pukka ALCO knobs are easy enough to find, but I haven't unearthed a source for proper RED Stackpole slide switches yet.

[pompeiisneaks]

Not by stackpole, but what about these: https://www.allparts.com/EP-0260-026-Re ... _5456.html

~Phil

[norburybrook]

wow, $5 each, I paid $0.30 each for black ones, they'll have to do for now.


M

[pompeiisneaks]

Actually this ones in the UK for you:

http://www.cdguitars.co.uk/slide-switch ... 1918-p.asp

same price range but shipping is likely better/faster/cheaper.

~Phil

[Mr. dB]

Actually this ones in the UK for you:

http://www.cdguitars.co.uk/slide-switch ... 1918-p.asp

same price range but shipping is likely better/faster/cheaper.

~Phil

And they come with screws.